In radiotelephones, the programme code of the object programme i.e. the operating software has conventionally been recorded into a permanent storage non-volatile memory e.g. a read-only-memory (ROM) or an erasable programmable ROM (EPROM) i.e. a memory in which the contents are not lost when the power supply is switched off. Such a solution is used when the object programmes cannot be loaded from an external memory, such as a diskette or similar, when switching on the radiotelephone. The use of a permanent memory, such as a ROM, is a satisfactory solution per se, but it is expensive if the recorded programmes have to be updated. When updating the object programme, the radiotelephone must be opened in order to replace the memory. If the memory has been installed by soldering, this replacement will require the services of a professional installer. Optionally, the medium is installed on the base, involving raised costs and space requirement. However, the updating of the storage is an onerous operation and usually the radiotelephone has to be taken to service for this.